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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
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 * accompanied this code).
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package java.lang.classfile.attribute;

import java.lang.classfile.Attribute;
import java.lang.classfile.ClassElement;
import java.lang.classfile.constantpool.Utf8Entry;
import jdk.internal.classfile.impl.BoundAttribute;
import jdk.internal.classfile.impl.TemporaryConstantPool;
import jdk.internal.classfile.impl.UnboundAttribute;
import jdk.internal.javac.PreviewFeature;

/**
 * Models the {@code CompilationID} attribute (@@@ need reference), which can
 * appear on classes and records the compilation time of the class.  Delivered
 * as a {@link java.lang.classfile.ClassElement} when traversing the elements of
 * a {@link java.lang.classfile.ClassModel}.
 * <p>
 * The attribute does not permit multiple instances in a given location.
 * Subsequent occurrence of the attribute takes precedence during the attributed
 * element build or transformation.
 *
 * @since 22
 */
@PreviewFeature(feature = PreviewFeature.Feature.CLASSFILE_API)
public sealed interface CompilationIDAttribute
        extends Attribute<CompilationIDAttribute>, ClassElement
        permits BoundAttribute.BoundCompilationIDAttribute,
                UnboundAttribute.UnboundCompilationIDAttribute {

    /**
     * {@return the compilation ID}  The compilation ID is the value of
     * {@link System#currentTimeMillis()} when the classfile is generated.
     */
    Utf8Entry compilationId();

    /**
     * {@return a {@code CompilationID} attribute}
     * @param id the compilation ID
     */
    static CompilationIDAttribute of(Utf8Entry id) {
        return new UnboundAttribute.UnboundCompilationIDAttribute(id);
    }

    /**
     * {@return a {@code CompilationID} attribute}
     * @param id the compilation ID
     */
    static CompilationIDAttribute of(String id) {
        return new UnboundAttribute.UnboundCompilationIDAttribute(TemporaryConstantPool.INSTANCE.utf8Entry(id));
    }
}
